1. Field of the Invention
This invention concerns a method and apparatus for manufacturing, in a continuous and uninterrupted process, imprinted laminated stock from continuous webs. A first web from uncoated stock is provided with a release coating and then joined to a second web for printing and processing for completion into a final laminated product.
2. Description of the Prior Art
It is well known in the art to run pre-laminated sheets through a printing and die cutting station to produce a final, imprinted product. Examples of such products include labels, coupons, and stickers where an imprinted top web is adhesively joined to a bottom web. The top web is removable from the bottom web or carrier sheet by virtue of a release coating which has been applied to the carrier sheet. Because the adhesive resists attachment to the coating, it instead adheres to the top web and allows the top web to be readily attached to another surface.
In the past, the final printed laminated web was in fact created in separate manufacturing steps. Typically, this involved the separate manufacture of the carrier sheet by providing raw or uncoated paper stock and then applying the release coating thereto. The carrier sheet was then stored and subsequently delivered to a second facility for adhesively joining to a top web which had been imprinted. In one example set forth in U.S. Pat. No. 4,661,189, a coated web was joined to a printed label stock by screen printing of adhesive to one of the webs before die cutting and stripping to produce a final product. The process required a carrier web to which a release coating had been applied. More recently, as shown for example in U.S. Pat. No. 5,021,273, the top web has been imprinted subsequent to joining the two webs together. However, the process illustrated therein required the provision of the first and second webs as a pre-laminated roll, and not as part of a continuous process beginning with uncoated webs.
While satisfactory final products have been produced in accordance with the teachings of the prior art, the processes have been inflexible and subject to accumulation of a variety of inventory of expensive, pre-laminated or pre-coated stock. The necessity of starting with raw paper, applying a silicone or other release coating, storing that roll until needed, and then transferring the roll with a release coating to a face stock printing, adhesive coating & laminating and die cutting press for mating with a face stock roll is time consuming, labor intensive, and requires additional transportation resources. Additionally, problems in controlling moisture changes in the webs during storage and processing have led to a need for remoisturizing the web during manufacture of the laminated stock. There has thus developed a need for a method and apparatus whereby essentially raw paper stock can be turned into an imprinted and laminated article in a single, continuous and uninterrupted process.